Feed grinder



June 15, 1965 J. YBERG 3,189,287

FEED GRINDER F1166. March 2, 1964 m I i 29 20 L l I9 22 x l E QIJ E r IIO ATTORNEY United States Patent will ansazsv FEMD GRINDER Jonas 3. Byherg, 511 N. Water 3h, ilverton, Greg. Filed Mar. 2, 1964, Ser. No. 348,536 Claims. ll. 241-475) grinding surfaces one of which rotates with respect to the other. The wear imposed on these grinding surfaces in time reduces their efficiency, affects the quality and consistency of the resulting grind, requires adjustments of the grinding elements and the employment of increased horsepower, and finally necessitates replacement of the grinding elements.

Another type of grinder extensively used for this purpose, and frequently for various reasons preferred to the burr mill type, is the hammer mill type in which hammers, attached to a driven rotating shaft, operate in a cylindrical screen chamber and subject the material delivered into the chamber to grinding impacts until it escapes through the screen openings. Here also there is the problem of wear on the edges and corners of the hammers and on the screen. Furthermore with this type thereis a considerable lack of uniformity in the grind since some kernels of grain will be driven through a screen opening almost immediately while similar kernels may ricochet back and forth in the screen chamber before finding an opening and be subjected to excessive grinding impacts in the meantime.

Lack of uniformity in the grinding of feed is a particular problem. The production of flour or too finely pulverized particles together with the coarse particles is especially undesirable since feed reduced to such fine consistency is in itself unsuitable for consumption by farm animals.

An object of the present invention is to provide an improved feed grinder with which a greater uniformity of grind is obtained.

A related object is to provide a grinder in which there is little or no likelihood of any excessive grinding occurring to the extent that any appreciable amount of flour can result. j

A further object of the invention is to provide an improved feed grinder which does not involve any serious Wear problem, and in which ordinary wear does not result in any decrease in elliciency.

An additional specific object is to provide a novel grinder, particularly suitable for feed grinding, in which no sharp corners or edges, which would ordinarily be subject to wear, are essential in the grinding.

Another object is to provide a feed grinder in which the inertia of the moving grain particles to be ground will be utilized to cause impacts sufiicient to produce the desired comminuting of the particles.

A still further object of this invention is to provide a novel and improved feed grinder which will be very simple in construction and which will present no maintenance problem.

The manner in which and the means by which these objects and other incidental advantages are attained will be readily understood from the following brief description with reference to the accompanying drawings.

tank 1th and in a bearing 26 located within the tubular '29 on the shaft of the motor M. Thus, as apparent from 3&39237 Patented June 15, 1965 "ice In the drawings:

FIG. 1 is a sectional elevation showing a feed grinder embodying the present invention;

FIG. 2 is a section on line 2-2 of FIG. 1 drawn to a larger scale; and

FIG. 3 is a section on line 3--3 of FIG. 1 drawn to the same scale as FIG. 2.

Referring first to FIG. 1, the device includes a tank 10 of standard or suitable size and shape for holding the grain to be ground. The tank is provided with suitable support means (not shown), and with a suitable inlet 11 at or near the top and suitable discharge outlet 12 with a control slide or shutter 13.

The top wall 14, of the tank is formed with a central cylindrical bearing housing 15, in which are a pair of support bearing assemblies 16 and 17. These bearing assemblies rotatably support a tubular shaft 18 to the bottom end of which is secured an annular rotor disc 19. A belt pulley 20 is secured on the top end of the tubular shaft 18 above the bearing housing 15 and has suitable belt connection 21 with a drive pulley 22 secured on the shaft of the motor M, the motor being mounted on the side of the tank 10.

An augendesignated in its entirety by the reference 23, includes an anger shaft 24 which extends upwardly from the bottom of the tank and through the tubular shaft 18 for the rotor disc 19 and terminates above the top of the tubular shaft 18. This auger shaft is rotatably mounted in a suitable bearing 25 at the bottom of the shaft 18. A pulley 27, secured at the top of the auger shaft, is connected by a belt 23 to a second drive pulley FIG. 1, the auger 23 and the rotor disc 19 are both driven from the motor M, but the rotor disc is driven at much greater speed.

A stationary conveyor tube 30 surrounds the auger 23 for most of its extent, the open bottom of this conveyor being located a short distance above the bottom end of the auger. The top end of this conveyor tube is attached to an annular plate 31 which is rigidly secured in position below the top wall 14 of the tank and below the rotor disc 19 by a plurality of hangers 32,. the rotor disc 19 and the annular plate 31 thus being positioned in parallel horizontal planes. The outer diameter of the annular plate 31 is greater than the outer diameter of the annular rotor. disc 19, and the inner diameter of the rotor disc 19 is less than the diameter of the conveyor tube 30 surrounding the auger.

A series of identical, equally spaced and substantially radially-extending impeller blades 33 are mounted on the underside or bottom face of the rotor disc 19 adjacent the outer periphery (see also FIGS. 2 and 3). These are fiat rectangular blades extending in vertical planes with their bottom edges spaced only a slight distance above the top face of the underlying stationary annular plate 31 for clearance. l

A series of similar identical, equally spaced flat anvil blades 34 are mounted on the top face of the stationary annular plate 31 adjacent its periphery. These blades 34 are spaced outwardly from the periphery of the rotor disc 19, and thus arespaced from the outer edges of the impeller blades 33 of the rotor disc a sufficient distance (for example, from A inch to one inch or so) so that no cutting or crushingof the feed grains between these two sets of blades occurs. The stationary anvil blades 34 are preferably taller than the impeller blades 33 and preferably are spaced closer together, as indicated in FIGS. 2 and 3.

As the grain or feed is carried up onto the inner portion of the stationary annular plate 31 by the operation of the auger 23 it is contacted by the impeller blades 33 of the rapidly rotating disc 19. These blades act to cause each grain particle to be thrown outwardly in a direction for the most part which will be tangent to the periphery of the rotating disc 19 at the point where the particle leaves the disc. Upon leaving the rotating disc the particle will strike the surface of a stationary anvil blade 34 and in turn be deflected outwardly, as indicated by the broken line X in FIG. 2.

The impact of the grain particles as they strike the stationary anvil blades results in the shattering or breaking up of the particles. Due to the fact that the larger particles-will strike the anvil blades with greater inertial effect the shattering effect produced on the larger size heavier particles will be greater than with the smaller particles, which, with the recirculation of the grain through the device, will tend largely to equalize the grind, or breaking up of the particles, and make it uniform. It will also be apparent that, since there is no simultaneous contact of the blades of the two sets with each particle, excessive grinding of some of the particles is not likely to occur, and the production of undesirable flour as incidental to the grinding is greatly minimized.

It will be'noted that the corners and edges of the blades play little part in the grinding action and that the particles strike the flat faces of the anvil blades to receive their shattering impacts. Consequently no sharpening of any edges or corners of the blades is required, and as long as the particles are thrust outwardly against the flat faces or broadsides of the anvil blades the grinder maintains its efficiency. Furthermore, as each particle strikes an anvil blade it Will be deflected outwardly, subsequently dropping back down into the tank. Consequently the individualparticles do not interfere with each other or do not get in the path of the on-coming particles, and there is no cushioning effect to reduce the effectiveness of the grinding as occurs, for example, with grinders of the hammer mill type.

Although a tank of a particular shape has been shown in FIG. 1, and although a familiar type of vertical, centrally positioned auger has been shown as the means for delivering the grain to the grinding means, various shapes of tanks may be used for the feed being ground, and also other means for bringing or delivering the feed to the impeller or velocity imparting blades of the rotor element could be employed without departing from the principle of the invention. It is not intended to limit the invention except as set forth in the claims.

I claim:

ll. In a feed grinder of the character described, a pair of co-axial discs spaced a short distance apart in parallel horizontal planes, at least one of said discs being an annular disc having a central opening, means for delivering feed to be ground through said central opening in said latter mentioned disc and into the space between said discs, means for holding the lower of said discs in stationary position, means rotatably supporting the upper of said discs, means for imparting rotation to said upper disc, said lower stationary disc having a greater outer diameter than said upper rotating disc, a series of equally spaced substantially rectangular impeller blades mounted on the lower face of said upper rotating disc, said blades positioned adjacent the periphery of said rotating disc, the edges of said blades adjacent said stationary disc terminating within a short clearance distance from said lower stationary disc, and a series of equally spaced substantially radially extending anvil blades mounted on the upper face of said stationary lower disc and positioned adjacent the periphery of said stationary low disc, the inner edges of said anvil blades on said stationary disc being spaced from the respective outer edges of said impeller blades on said rotating disc by a distance of not less than approximately one-quarter inch.

2. A feed grinder including a tank, a rotating auger in said tank, a conveyor tube surrounding said auger, a pair of coaxial discs spaced a short distance apart in parallel horizontal planes and located near the top of the tank co-axial with the auger and conveyor tube, the lower of said discs being an annular disc having a central opening, means holding said lower disc in stationary position, the auger and conveyor tube leading to said lower disc, means rotatably supporting the upper of said discs, means for imparting rotation to said upper disc, said lower stationary disc having a greater outer peripheral diameter than said upper rotating disc, a series of equally spaced impeller blades mounted on the lower face of said upper rotating disc, said blades positioned adjacent the periphery of said rotating disc, the edges of said blades adjacent said lower stationary disc terminating within a short clearance from said stationary disc, and a series of equally spaced substantially rectangular anvil blades mounted on the upper face of said stationary lower disc and positioned adjacent the outer periphery of said lower disc, the inner edges of said anvil blades on said stationary disc being spaced from the respective outer edges of said impeller blades on said rotating disc by a distance of not less than one-quarter inch.

3. The combination set forth in claim 2 with said anvil blades on said stationary lower disc being spaced closer together than said impeller blades on said upper rotating disc.

4. The combination set forth in claim 2 with said anvil blades on said stationary lower disc extending up beyond the level of the bottom face of said upper rotating disc and with said anvil blades spaced closer together than said impeller blades on said rotating disc.

5. A feed grinder including a tank, an inlet and outlet for the tank, a pair of co-axial discs spaced a short distance apart in parallel horizontal planes positioned near the top of the tank, said discs being annular discs having central openings, the lower of said discs having a larger central opening than the upper of said discs, said lower disc being stationary, said upper disc being rotatable, a rotating auger in said tank leading up to said stationary lower disc, a conveyor tube in said tank surrounding said auger, the top of said conveyor tube secured to said annular stationary lower disc, hangers in said tank for supporting said stationary lower disc and conveyor tube, said lower stationary disc having a greater outer peripheral diameter than said upper rotating disc, a series of equally spaced substantially radially extending rectangular impeller blades mounted on the lower race of said upper rotating disc, said blades positioned adjacent the outer periphery of said rotating disc, the bottom edges of said blades adjacent said stationary disc terminating within a short clearance distance from said lower stationary disc, a series of equally spaced substantially rectangular anvil blades mounted on the upper face of said stationary lower disc and positioned adjacent the outer periphery of said stationary lower disc, the inner edges of said anvil blades on said stationary lower disc being spaced from the respective outer edges of said impeller blades on said rotating disc by a distance of not less than approximately one-quarter inch, means for rotating said auger, and associated means for rotating said upper disc at a greater speed than said auger, whereby feed in the tank will be delivered onto said stationary disc by said auger and thereby brought into contact with said impeller blades and said impeller blades will cause the feed to be thrown against said anvil blades.

References Cited by the Examiner UNITED STATES PATENTS 1,636,033 7/27 Agnew 241-275 X 2,428,670 10/47 Hulse 241-275 X 2,840,357 6/58 Nauta 241-275 X ANDREW R. JUHASZ, Primary Examiner. 

1. IN A FEED GRINDER OF THE CHARACTER DESCRIBED, A PAIR OF CO-AXIAL DISC SPACED A SHORT DISTANCE APART IN PARALLEL HORIZONTAL PLANES, AT LEAST ONE OF SAID DISCS BEING AN ANNULAR DISC HAVING A CENTRAL OPENING, MEANS FOR DELIVERING FEED TO BE GROUND THROUGH SAID CENTRAL OPENING IN SAID LATTER MENTIONED DISC AND INTO THE SPACE BETWEEN IN STATIONDISCS, MEANS FOR HOLDING THE LOWER OF SAID DISCS IN STATIONARY POSITION, MEANS ROTATABLY SUPPORTING THE UPPER OF SAID DISCS, MEANS FOR IMPARTING ROTATION TO SAID UPPER DISC, AND LOWER STATIONARY DISC HAVING A GREATER OUTER DIAMETER THAN SAID UPPER ROTATING DISC, A SERIES OF EQUALLY SPACED SUBSTANTIALLY RECTANGULAR IMPELLER BLADES MOUNTED ON THE LOWER FACE OF SAID UPPER ROTATING DISC, SAID BLADES POSITIONED ADJACENT THE PERIPHERY OF SAID ROTATING DISC, THE EDGES OF SAID BLADES ADJACENT SAID STATIONARY DISC TERMINATING WITHIN A SHORT CLEARANCE DISTANCE FROM SAID LOWER STATIONARY DISC, AND A SERIES OF EQUALLY SPACED SUBSTANTIALLY RADIALLY EXTENDING ANVIL BLADES MOUNTED ON THE UPPER FACE OF SAID STATIONARY LOWER DISC AND POSITIONED ADJACENT THE PERIPHERY OF SAID STATIONARY LOW DISC, THE INNER EDGES OF SAID ANVIL BLADES ON SAID STATIONARY DISC BEING SPACED FROM THE RESPECTIVE OUTER EDGES OF SAID IMPELLER BLADES ON SAID ROTATING DISC BY A DISTANCE OF NOT LESS THAN APPROXIMATELY ONE-QUARTER INCH. 